my $format = "foo (bar] baz"; 
eval '$regex = qr/$format/;'; 
die "ack - $@" if $@;

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Danger! Danger! If $format contains a slash, that ends the regex and begins Perl again.

I think you were trying for this: 

my $format = "foo (bar] baz"; 
eval { qr/$format/ };
die "ack - $@" if $@;

[download]
Which won't matter if it contains slashes. Almost every code that contains string-eval is broken, and almost never necessary. {grin}

-- Randal L. Schwartz, Perl hacker

update: Oh duh. Didn't see the single quotes. In which case, it's overkill, but not dangerous as-is, except that it can be misleading as to why you used single quotes and run-time eval-string instead of compile-time eval-block.

In reply to • DANGER! Re: Re: How to identify invalid reg. expr.? by merlyn
in thread How to identify invalid reg. expr.? by armyk

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